IW44Image.h

//C- -*- C++ -*-//C- -------------------------------------------------------------------//C- DjVuLibre-3.5//C- Copyright (c) 2002 Leon Bottou and Yann Le Cun.//C- Copyright (c) 2001 AT&T//C-//C- This software is subject to, and may be distributed under, the//C- GNU General Public License, either Version 2 of the license,//C- or (at your option) any later version. The license should have//C- accompanied the software or you may obtain a copy of the license//C- from the Free Software Foundation at http://www.fsf.org .//C-//C- This program is distributed in the hope that it will be useful,//C- but WITHOUT ANY WARRANTY; without even the implied warranty of//C- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the//C- GNU General Public License for more details.//C- //C- DjVuLibre-3.5 is derived from the DjVu(r) Reference Library from//C- Lizardtech Software. Lizardtech Software has authorized us to//C- replace the original DjVu(r) Reference Library notice by the following//C- text (see doc/lizard2002.djvu and doc/lizardtech2007.djvu)://C-//C- ------------------------------------------------------------------//C- | DjVu (r) Reference Library (v. 3.5)//C- | Copyright (c) 1999-2001 LizardTech, Inc. All Rights Reserved.//C- | The DjVu Reference Library is protected by U.S. Pat. No.//C- | 6,058,214 and patents pending.//C- |//C- | This software is subject to, and may be distributed under, the//C- | GNU General Public License, either Version 2 of the license,//C- | or (at your option) any later version. The license should have//C- | accompanied the software or you may obtain a copy of the license//C- | from the Free Software Foundation at http://www.fsf.org .//C- |//C- | The computer code originally released by LizardTech under this//C- | license and unmodified by other parties is deemed "the LIZARDTECH//C- | ORIGINAL CODE." Subject to any third party intellectual property//C- | claims, LizardTech grants recipient a worldwide, royalty-free, //C- | non-exclusive license to make, use, sell, or otherwise dispose of //C- | the LIZARDTECH ORIGINAL CODE or of programs derived from the //C- | LIZARDTECH ORIGINAL CODE in compliance with the terms of the GNU //C- | General Public License. This grant only confers the right to //C- | infringe patent claims underlying the LIZARDTECH ORIGINAL CODE to //C- | the extent such infringement is reasonably necessary to enable //C- | recipient to make, have made, practice, sell, or otherwise dispose //C- | of the LIZARDTECH ORIGINAL CODE (or portions thereof) and not to //C- | any greater extent that may be necessary to utilize further //C- | modifications or combinations.//C- |//C- | The LIZARDTECH ORIGINAL CODE is provided "AS IS" WITHOUT WARRANTY//C- | OF ANY KIND, EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED//C- | TO ANY WARRANTY OF NON-INFRINGEMENT, OR ANY IMPLIED WARRANTY OF//C- | MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.//C- +------------------------------------------------------------------// // $Id: IW44Image.h,v 1.13 2007/05/19 03:07:34 leonb Exp $// $Name: debian_version_3_5_20-7 $#ifndef IW44IMAGE_H_#define IW44IMAGE_H_#ifdef HAVE_CONFIG_H#include "config.h"#endif#if NEED_GNUG_PRAGMAS# pragma interface#endif/** @name IW44Image.h Files #"IW44Image.h"# and #"IW44Image.cpp"# implement the DjVu IW44 wavelet scheme for the compression of gray-level images (see class \Ref{IWBitmap}) and color images (see class \Ref{IWPixmap}). Programs \Ref{c44} and \Ref{d44} demonstrate how to encode and decode IW44 files. {\bf IW44 File Structure} --- The IW44 files are structured according to the EA IFF85 specifications (see \Ref{IFFByteStream.h}). Gray level IW44 Images consist of a single #"FORM:BM44"# chunk composed of an arbitrary number of #"BM44"# data chunks. Color IW44 Images consist of a single #"FORM:PM44"# chunk composed of an arbitrary number of #"PM44"# data chunks. The successive #"PM44"# or #"BM44"# data chunks contain successive refinements of the encoded image. Each chunk contains a certain number of ``data slices''. The first chunk also contains a small image header. You can use program \Ref{djvuinfo} to display all this structural information: \begin{verbatim} % djvuinfo lag.iw4 lag.iw4: FORM:PM44 [62598] PM44 [10807] #1 - 74 slices - v1.2 (color) - 684x510 PM44 [23583] #2 - 13 slices PM44 [28178] #3 - 10 slices \end{verbatim} {\bf Embedded IW44 Images} --- These IW44 data chunks can also appear within other contexts. Files representing a DjVu page, for instance, consist of a single #"FORM:DJVU"# composite chunk. This composite chunk may contain #"BG44"# chunks encoding the background layer and #"FG44"# chunks encoding the foreground color layer. These #"BG44"# and #"FG44"# chunks are actually regular IW44 data chunks with a different chunk identifier. This information too can be displayed using program \Ref{djvuinfo}. \begin{verbatim} % djvuinfo graham1.djvu graham1.djvu: FORM:DJVU [32553] INFO [5] 3156x2325, version 17 Sjbz [17692] BG44 [2570] #1 - 74 slices - v1.2 (color) - 1052x775 FG44 [1035] #1 - 100 slices - v1.2 (color) - 263x194 BG44 [3048] #2 - 10 slices BG44 [894] #3 - 4 slices BG44 [7247] #4 - 9 slices \end{verbatim} {\bf Performance} --- The main design objective for the DjVu wavelets consisted of allowing progressive rendering and smooth scrolling of large images with limited memory requirements. Decoding functions process the compressed data and update a memory efficient representation of the wavelet coefficients. Imaging function then can quickly render an arbitrary segment of the image using the available data. Both process can be carried out in two threads of execution. This design plays an important role in the DjVu system. We have investigated various state-of-the-art wavelet compression schemes: although these schemes may achieve slightly smaller file sizes, the decoding functions did not even approach our requirements. The IW44 wavelets satisfy these requirements today. It performs very well for quality settings resulting in high compression ratios. It should not be used for quasi-lossless compression because certain design choices deliberately sacrifice the IW44 quasi-lossless performance in order to improve the image quality at high compression ratios. Little care however has been taken to make the IW44 encoder memory efficient. This code uses two copies of the wavelet coefficient data structure (one for the raw coefficients, one for the quantized coefficients). A more sophisticated implementation should considerably reduce the memory requirements. {\bf Masking} --- When we create a DjVu image, we often know that certain pixels of the background image are going to be covered by foreground objects like text or drawings. The DjVu IW44 wavelet decomposition routine can use an optional bilevel image named the mask. Every non zero pixel in the mask means the value of the corresponding pixel in the background image is irrelevant. The wavelet decomposition code will replace these masked pixels by a color value whose coding cost is minimal (see \URL{http://www.research.att.com/~leonb/DJVU/mask}). {\bf ToDo} --- There are many improvements to be made. Besides better quantization algorithms (such as trellis quantization and bitrate allocation), we should allow for more wavelet transforms. These improvements may be implemented in future version, if (and only if) they can meet our decoding constraints. Future versions will probably split file #"IW44Image.cpp"# which currently contains everything. @memo Wavelet encoded images. @author L\'eon Bottou <leonb@research.att.com>// From: Leon Bottou, 1/31/2002// Lizardtech has split the corresponding cpp file into a decoder and an encoder.// Only superficial changes. The meat is mine. @version #$Id: IW44Image.h,v 1.13 2007/05/19 03:07:34 leonb Exp $# *///@{#include "GSmartPointer.h"#include "ZPCodec.h"#ifdef HAVE_NAMESPACESnamespace DJVU {
# ifdef NOT_DEFINED // Just to fool emacs c++ mode}
#endif#endifclass GRect;
class IFFByteStream;
class ByteStream;
class GBitmap;
class GPixmap;
/** IW44 encoding parameters. This data structure gathers the quality specification parameters needed for encoding each chunk of an IW44 file. Chunk data is generated until meeting either the slice target, the size target or the decibel target. */00193struct DJVUAPI IWEncoderParms
{ /** Slice target. Data generation for the current chunk stops if the total number of slices (in this chunk and all the previous chunks) reaches value #slice#. The default value #0# has a special meaning: data will be generated regardless of the number of slices in the file. */00199int slices; /** Size target. Data generation for the current chunk stops if the total data size (in this chunk and all the previous chunks), expressed in bytes, reaches value #size#. The default value #0# has a special meaning: data will be generated regardless of the file size. */00204int bytes; /** Decibel target. Data generation for the current chunk stops if the estimated luminance error, expressed in decibels, reaches value #decibel#. The default value #0# has a special meaning: data will be generated regardless of the estimated luminance error. Specifying value #0# in fact shortcuts the computation of the estimated luminance error and sensibly speeds up the encoding process. */00211float decibels; /** Constructor. Initializes the structure with the default values. */IWEncoderParms(void);
};
/** IW44 encoded gray-level and color images. This class acts as a base for images represented as a collection of IW44 wavelet coefficients. The coefficients are stored in a memory efficient data structure. Member function \Ref{get_bitmap} renders an arbitrary segment of the image into a \Ref{GBitmap}. Member functions \Ref{decode_iff} and \Ref{encode_iff} read and write DjVu IW44 files (see \Ref{IW44Image.h}). Both the copy constructor and the copy operator are declared as private members. It is therefore not possible to make multiple copies of instances of this class. */00228class DJVUAPI IW44Image : publicGPEnabled
{
public: /** Chrominance processing selector. The following constants may be used as argument to the following \Ref{IWPixmap} constructor to indicate how the chrominance information should be processed. There are four possible values: \begin{description} \item[CRCBnone:] The wavelet transform will discard the chrominance information and only keep the luminance. The image will show in shades of gray. \item[CRCBhalf:] The wavelet transform will process the chrominance at only half the image resolution. This option creates smaller files but may create artifacts in highly colored images. \item[CRCBnormal:] The wavelet transform will process the chrominance at full resolution. This is the default. \item[CRCBfull:] The wavelet transform will process the chrominance at full resolution. This option also disables the chrominance encoding delay (see \Ref{parm_crcbdelay}) which usually reduces the bitrate associated with the chrominance information. \end{description} */00247enumCRCBMode {
CRCBnone,
CRCBhalf,
CRCBnormal,
CRCBfull };
class Transform;
class Map;
class Block;
class Codec;
struct Alloc;
struct PrimaryHeader;
struct SecondaryHeader;
struct TertiaryHeader;
enum ImageType {
GRAY=false,
COLOR=true };
protected:
IW44Image(void);
public: /** Null constructor. Constructs an empty IW44Image object. This object does not contain anything meaningful. You must call function \Ref{init}, \Ref{decode_iff} or \Ref{decode_chunk} to populate the wavelet coefficient data structure. You may not use \Ref{encode_iff} or \Ref{encode_chunk}. */staticGP<IW44Image> create_decode(const ImageType itype=COLOR); /** Null constructor. Constructs an empty IW44Image object. This object does not contain anything meaningful. You must call function \Ref{init}, \Ref{decode_iff} or \Ref{decode_chunk} to populate the wavelet coefficient data structure. You may then use \Ref{encode_iff} and \Ref{encode_chunk}. */staticGP<IW44Image> create_encode(const ImageType itype=COLOR);
// virtual destructorvirtual ~IW44Image(); /** Initializes an IWBitmap with image #bm#. This constructor performs the wavelet decomposition of image #bm# and records the corresponding wavelet coefficient. Argument #mask# is an optional bilevel image specifying the masked pixels (see \Ref{IW44Image.h}). */staticGP<IW44Image> create_encode(constGBitmap &bm, constGP<GBitmap> mask=0); /** Initializes an IWPixmap with color image #bm#. This constructor performs the wavelet decomposition of image #bm# and records the corresponding wavelet coefficient. Argument #mask# is an optional bilevel image specifying the masked pixels (see \Ref{IW44Image.h}). Argument #crcbmode# specifies how the chrominance information should be encoded (see \Ref{CRCBMode}). */staticGP<IW44Image> create_encode(constGPixmap &bm, constGP<GBitmap> mask=0, CRCBMode crcbmode=CRCBnormal);
// ACCESS /** Returns the width of the IWBitmap image. */int get_width(void) const; /** Returns the height of the IWBitmap image. */int get_height(void) const; /** Reconstructs the complete image. The reconstructed image is then returned as a GBitmap object. */00299virtualGP<GBitmap> get_bitmap(void) {return 0;} /** Reconstructs a segment of the image at a given scale. The subsampling ratio #subsample# must be a power of two between #1# and #32#. Argument #rect# specifies which segment of the subsampled image should be reconstructed. The reconstructed image is returned as a GBitmap object whose size is equal to the size of the rectangle #rect#. */00305virtualGP<GBitmap> get_bitmap(int subsample, constGRect &rect) {return 0;} /** Reconstructs the complete image. The reconstructed image is then returned as a GPixmap object. */00308virtualGP<GPixmap> get_pixmap(void) {return 0;} /** Reconstructs a segment of the image at a given scale. The subsampling ratio #subsample# must be a power of two between #1# and #32#. Argument #rect# specifies which segment of the subsampled image should be reconstructed. The reconstructed image is returned as a GPixmap object whose size is equal to the size of the rectangle #rect#. */00314virtualGP<GPixmap> get_pixmap(int subsample, constGRect &rect) {return 0;} /** Returns the amount of memory used by the wavelet coefficients. This amount of memory is expressed in bytes. */virtualunsignedint get_memory_usage(void) const = 0; /** Returns the filling ratio of the internal data structure. Wavelet coefficients are stored in a sparse array. This function tells what percentage of bins have been effectively allocated. */virtualint get_percent_memory(void) const = 0;
// CODER /** Encodes one data chunk into ByteStream #bs#. Parameter #parms# controls how much data is generated. The chunk data is written to ByteStream #bs# with no IFF header. Successive calls to #encode_chunk# encode successive chunks. You must call #close_codec# after encoding the last chunk of a file. */virtualint encode_chunk(GP<ByteStream> gbs, constIWEncoderParms &parms); /** Writes a gray level image into DjVu IW44 file. This function creates a composite chunk (identifier #FORM:BM44# or #FORM:PM44#) composed of #nchunks# chunks (identifier #BM44# or #PM44#). Data for each chunk is generated with #encode_chunk# using the corresponding parameters in array #parms#. */virtualvoid encode_iff(IFFByteStream &iff, int nchunks, constIWEncoderParms *parms);
// DECODER /** Decodes one data chunk from ByteStream #bs#. Successive calls to #decode_chunk# decode successive chunks. You must call #close_codec# after decoding the last chunk of a file. Note that function #get_bitmap# and #decode_chunk# may be called simultaneously from two execution threads. */virtualint decode_chunk(GP<ByteStream> gbs) = 0; /** This function enters a composite chunk (identifier #FORM:BM44#, or #FORM:PM44#), and decodes a maximum of #maxchunks# data chunks (identifier #BM44#). Data for each chunk is processed using the function #decode_chunk#. */virtualvoid decode_iff(IFFByteStream &iff, int maxchunks=999) = 0;
// MISCELLANEOUS /** Resets the encoder/decoder state. The first call to #decode_chunk# or #encode_chunk# initializes the coder for encoding or decoding. Function #close_codec# must be called after processing the last chunk in order to reset the coder and release the associated memory. */virtualvoid close_codec(void) = 0; /** Returns the chunk serial number. This function returns the serial number of the last chunk encoded with #encode_chunk# or decoded with #decode_chunk#. The first chunk always has serial number #1#. Successive chunks have increasing serial numbers. Value #0# is returned if this function is called before calling #encode_chunk# or #decode_chunk# or after calling #close_codec#. */virtualint get_serial(void) = 0; /** Sets the chrominance delay parameter. This function can be called before encoding the first color IW44 data chunk. Parameter #parm# is an encoding delay which reduces the bitrate associated with the chrominance information. The default chrominance encoding delay is 10. */00364virtualint parm_crcbdelay(constint parm) {return parm;} /** Sets the #dbfrac# parameter. This function can be called before encoding the first IW44 data chunk. Parameter #frac# modifies the decibel estimation algorithm in such a way that the decibel target only pertains to the average error of the fraction #frac# of the most misrepresented 32x32 pixel blocks. Setting arguments #frac# to #1.0# restores the normal behavior. */virtualvoid parm_dbfrac(float frac) = 0;
protected:
// Parameterfloat db_frac;
// Data
Map *ymap, *cbmap, *crmap;
int cslice;
int cserial;
int cbytes;
private:
// Disable assignment semanticIW44Image(constIW44Image &ref);
IW44Image& operator=(constIW44Image &ref);
};
#ifdef IW44IMAGE_IMPLIMENTATION/*x IW44 encoded gray-level image. This class provided functions for managing a gray level image represented as a collection of IW44 wavelet coefficients. The coefficients are stored in a memory efficient data structure. Member function \Ref{get_bitmap} renders an arbitrary segment of the image into a \Ref{GBitmap}. Member functions \Ref{decode_iff} and \Ref{encode_iff} read and write DjVu IW44 files (see \Ref{IW44Image.h}). Both the copy constructor and the copy operator are declared as private members. It is therefore not possible to make multiple copies of instances of this class. */class DJVUAPI IWBitmap : publicIW44Image
{
public:
friendclass IW44Image;
class Encode;
protected:
/*x Null constructor. Constructs an empty IWBitmap object. This object does not contain anything meaningful. You must call function \Ref{init}, \Ref{decode_iff} or \Ref{decode_chunk} to populate the wavelet coefficient data structure. */
IWBitmap(void);
public:
//x virtual destructorvirtual ~IWBitmap();
//x ACCESS/*x Reconstructs the complete image. The reconstructed image is then returned as a GBitmap object. */virtualGP<GBitmap>get_bitmap(void);
/*x Reconstructs a segment of the image at a given scale. The subsampling ratio #subsample# must be a power of two between #1# and #32#. Argument #rect# specifies which segment of the subsampled image should be reconstructed. The reconstructed image is returned as a GBitmap object whose size is equal to the size of the rectangle #rect#. */virtualGP<GBitmap>get_bitmap(int subsample, constGRect &rect);
/*x Returns the amount of memory used by the wavelet coefficients. This amount of memory is expressed in bytes. */virtualunsignedintget_memory_usage(void) const;
/*x Returns the filling ratio of the internal data structure. Wavelet coefficients are stored in a sparse array. This function tells what percentage of bins have been effectively allocated. */virtualintget_percent_memory(void) const;
// DECODER/*x Decodes one data chunk from ByteStream #bs#. Successive calls to #decode_chunk# decode successive chunks. You must call #close_codec# after decoding the last chunk of a file. Note that function #get_bitmap# and #decode_chunk# may be called simultaneously from two execution threads. */virtualintdecode_chunk(GP<ByteStream> gbs);
/*x Reads a DjVu IW44 file as a gray level image. This function enters a composite chunk (identifier #FORM:BM44#), and decodes a maximum of #maxchunks# data chunks (identifier #BM44#). Data for each chunk is processed using the function #decode_chunk#. */virtualvoiddecode_iff(IFFByteStream &iff, int maxchunks=999);
// MISCELLANEOUS/*x Resets the encoder/decoder state. The first call to #decode_chunk# or #encode_chunk# initializes the coder for encoding or decoding. Function #close_codec# must be called after processing the last chunk in order to reset the coder and release the associated memory. */virtualvoidclose_codec(void);
/*x Returns the chunk serial number. This function returns the serial number of the last chunk encoded with #encode_chunk# or decoded with #decode_chunk#. The first chunk always has serial number #1#. Successive chunks have increasing serial numbers. Value #0# is returned if this function is called before calling #encode_chunk# or #decode_chunk# or after calling #close_codec#. */virtualintget_serial(void);
/*x Sets the #dbfrac# parameter. This function can be called before encoding the first IW44 data chunk. Parameter #frac# modifies the decibel estimation algorithm in such a way that the decibel target only pertains to the average error of the fraction #frac# of the most misrepresented 32x32 pixel blocks. Setting arguments #frac# to #1.0# restores the normal behavior. */virtualvoidparm_dbfrac(float frac);
private:
Codec *ycodec;
};
/*x IW44 encoded color image. This class provided functions for managing a color image represented as a collection of IW44 wavelet coefficients. The coefficients are stored in a memory efficient data structure. Member function \Ref{get_pixmap} renders an arbitrary segment of the image into a \Ref{GPixmap}. Member functions \Ref{decode_iff} and \Ref{encode_iff} read and write DjVu IW44 files (see \Ref{IW44Image.h}). Both the copy constructor and the copy operator are declared as private members. It is therefore not possible to make multiple copies of instances of this class. */class DJVUAPI IWPixmap : publicIW44Image
{
public:
friendclass IW44Image;
protected:
class Encode;
/*x Null constructor. Constructs an empty IWPixmap object. This object does not contain anything meaningful. You must call function \Ref{init}, \Ref{decode_iff} or \Ref{decode_chunk} to populate the wavelet coefficient data structure. */
IWPixmap(void);
public:
// virtual destructorvirtual ~IWPixmap();
// ACCESS/*x Reconstructs the complete image. The reconstructed image is then returned as a GPixmap object. */virtualGP<GPixmap>get_pixmap(void);
/*x Reconstructs a segment of the image at a given scale. The subsampling ratio #subsample# must be a power of two between #1# and #32#. Argument #rect# specifies which segment of the subsampled image should be reconstructed. The reconstructed image is returned as a GPixmap object whose size is equal to the size of the rectangle #rect#. */virtualGP<GPixmap>get_pixmap(int subsample, constGRect &rect);
/*x Returns the amount of memory used by the wavelet coefficients. This amount of memory is expressed in bytes. */virtualunsignedintget_memory_usage(void) const;
/*x Returns the filling ratio of the internal data structure. Wavelet coefficients are stored in a sparse array. This function tells what percentage of bins have been effectively allocated. */virtualintget_percent_memory(void) const;
// DECODER/*x Decodes one data chunk from ByteStream #bs#. Successive calls to #decode_chunk# decode successive chunks. You must call #close_codec# after decoding the last chunk of a file. Note that function #get_bitmap# and #decode_chunk# may be called simultaneously from two execution threads. */virtualintdecode_chunk(GP<ByteStream> gbs);
/*x Reads a DjVu IW44 file as a color image. This function enters a composite chunk (identifier #FORM:PM44# or #FORM:BM44#), and decodes a maximum of #maxchunks# data chunks (identifier #PM44# or #BM44#). Data for each chunk is processed using the function #decode_chunk#. */virtualvoiddecode_iff(IFFByteStream &iff, int maxchunks=999);
// MISCELLANEOUS/*x Resets the encoder/decoder state. The first call to #decode_chunk# or #encode_chunk# initializes the coder for encoding or decoding. Function #close_codec# must be called after processing the last chunk in order to reset the coder and release the associated memory. */virtualvoidclose_codec(void);
/*x Returns the chunk serial number. This function returns the serial number of the last chunk encoded with #encode_chunk# or decoded with #decode_chunk#. The first chunk always has serial number #1#. Successive chunks have increasing serial numbers. Value #0# is returned if this function is called before calling #encode_chunk# or #decode_chunk# or after calling #close_codec#. */virtualintget_serial(void);
/*x Sets the chrominance delay parameter. This function can be called before encoding the first IW44 data chunk. Parameter #parm# is an encoding delay which reduces the bitrate associated with the chrominance information. The default chrominance encoding delay is 10. */virtualintparm_crcbdelay(constint parm);
/*x Sets the #dbfrac# parameter. This function can be called before encoding the first IW44 data chunk. Parameter #frac# modifies the decibel estimation algorithm in such a way that the decibel target only pertains to the average error of the fraction #frac# of the most misrepresented 32x32 pixel blocks. Setting arguments #frac# to #1.0# restores the normal behavior. */virtualvoidparm_dbfrac(float frac);
protected:
// Parameterint crcb_delay;
int crcb_half;
// Dataprivate:
Codec *ycodec, *cbcodec, *crcodec;
};
/*x IW44Transform.*/class IW44Image::Transform
{
public:
class Decode;
class Encode;
protected:
staticvoid filter_begin(int w, int h);
staticvoid filter_end(void);
};
struct GPixel;
class IW44Image::Transform::Decode : publicIW44Image::Transform
{
public:
// WAVELET TRANSFORM/*x Forward transform. */staticvoid backward(short *p, int w, int h, int rowsize, int begin, int end);
// COLOR TRANSFORM/*x Converts YCbCr to RGB. */staticvoid YCbCr_to_RGB(GPixel *p, int w, int h, int rowsize);
};
//---------------------------------------------------------------// *** Class IW44Image::Block [declaration]// Represents a block of 32x32 coefficients after zigzagging and scalingclass IW44Image::Block // DJVU_CLASS
{
public:
// creating
Block(void);
// accessing scaled coefficientsshortget(int n) const;
voidset(int n, int val, IW44Image::Map *map);
// converting from liftblockvoid read_liftblock(constshort *coeff, IW44Image::Map *map);
void write_liftblock(short *coeff, int bmin=0, int bmax=64) const;
// sparse array accessconstshort* data(int n) const;
short* data(int n, IW44Image::Map *map);
void zero(int n);
// sparse representationprivate:
short **(pdata[4]);
};
//---------------------------------------------------------------// *** Class IW44Image::Map [declaration]// Represents all the blocks of an imageclass IW44Image::Map // DJVU_CLASS
{
public:
class Encode;
// construction
Map(int w, int h);
~Map();
// image accessvoid image(signedchar *img8, int rowsize,
int pixsep=1, int fast=0);
void image(int subsample, constGRect &rect,
signedchar *img8, int rowsize,
int pixsep=1, int fast=0);
// array of blocks
IW44Image::Block *blocks;
// geometryint iw, ih;
int bw, bh;
int nb;
// coefficient allocation stuffshort *alloc(int n);
short **allocp(int n);
IW44Image::Alloc *chain;
int top;
// statisticsint get_bucket_count(void) const;
unsignedintget_memory_usage(void) const;
};
//////////////////////////////////////////////////////// ENCODING/DECODING WAVELET COEFFICIENTS // USING HIERARCHICAL SET DIFFERENCE////////////////////////////////////////////////////////-----------------------------------------------// Class IW44Image::Codec [declaration+implementation]// Maintains information shared while encoding or decodingclass IW44Image::Codec
{
public:
class Decode;
class Encode;
protected:
// Construction
Codec(IW44Image::Map &map);
public:
virtual ~Codec();
// Codingint finish_code_slice(ZPCodec &zp);
virtualint code_slice(ZPCodec &zp) = 0;
// Data
IW44Image::Map &map; // working map// statusint curband; // current bandint curbit; // current bitplane// quantization tablesint quant_hi[10]; // quantization for bands 1 to 9int quant_lo[16]; // quantization for band 0.// bucket statechar coeffstate[256];
char bucketstate[16];
enum { ZERO = 1, // this coeff never hits this bit
ACTIVE = 2, // this coeff is already active
NEW = 4, // this coeff is becoming active
UNK = 8 }; // this coeff may become active// coding context
BitContext ctxStart [32];
BitContext ctxBucket[10][8];
BitContext ctxMant;
BitContext ctxRoot;
// helperint is_null_slice(int bit, int band);
int decode_prepare(int fbucket, int nbucket, IW44Image::Block &blk);
void decode_buckets(ZPCodec &zp, int bit, int band,
IW44Image::Block &blk, int fbucket, int nbucket);
};
//////////////////////////////////////////////////////// DEFINITION OF CHUNK HEADERS//////////////////////////////////////////////////////struct IW44Image::PrimaryHeader {
unsignedchar serial;
unsignedchar slices;
void encode(GP<ByteStream> gbs);
void decode(GP<ByteStream> gbs);
};
struct IW44Image::SecondaryHeader {
unsignedchar major;
unsignedchar minor;
void encode(GP<ByteStream> gbs);
void decode(GP<ByteStream> gbs);
};
struct IW44Image::TertiaryHeader {
unsignedchar xhi, xlo;
unsignedchar yhi, ylo;
unsignedchar crcbdelay;
void encode(GP<ByteStream> gbs);
void decode(GP<ByteStream> gbs, int major=1, int minor=2);
};
inlineconstshort*
IW44Image::Block::data(int n) const{
if (! pdata[n>>4])
return 0;
return pdata[n>>4][n&15];
}
inlineshort*
IW44Image::Block::data(int n, IW44Image::Map *map)
{
if (! pdata[n>>4])
pdata[n>>4] = map->allocp(16);
if (! pdata[n>>4][n &15])
pdata[n>>4][n &15] = map->alloc(16);
return pdata[n>>4][n&15];
}
inlineshort
IW44Image::Block::get(int n) const{
int n1 = (n>>4);
constshort *d = data(n1);
if (! d)
return 0;
return d[n&15];
}
inlinevoid
IW44Image::Block::set(int n, int val, IW44Image::Map *map)
{
int n1 = (n>>4);
short* d = data(n1, map);
d[n&15] = val;
}
#endif /* IW44IMAGE_IMPLIMENTATION *///@}#ifdef HAVE_NAMESPACES}
# ifndef NOT_USING_DJVU_NAMESPACEusing namespace DJVU;
# endif#endif#endif